Merge remote-tracking branch 'remotes/dgibson/tags/ppc-for-2.12-20180129' into staging

ppc patch queue 2018-01-29

Here's another batch of patches for ppc, spapr and related things.
Higlights:

  * Implement (with a bunch of necessary infrastructure) a hypercall
    to let guests properly apply Spectre and Meltdown workarounds.
  * Convert a number of old devices to trace events
  * Fix some bugs

# gpg: Signature made Mon 29 Jan 2018 03:27:30 GMT
# gpg:                using RSA key 0x6C38CACA20D9B392
# gpg: Good signature from "David Gibson <david@gibson.dropbear.id.au>"
# gpg:                 aka "David Gibson (Red Hat) <dgibson@redhat.com>"
# gpg:                 aka "David Gibson (ozlabs.org) <dgibson@ozlabs.org>"
# gpg:                 aka "David Gibson (kernel.org) <dwg@kernel.org>"
# Primary key fingerprint: 75F4 6586 AE61 A66C C44E  87DC 6C38 CACA 20D9 B392

* remotes/dgibson/tags/ppc-for-2.12-20180129:
  target/ppc/spapr: Add H-Call H_GET_CPU_CHARACTERISTICS
  target/ppc/spapr_caps: Add new tristate cap safe_indirect_branch
  target/ppc/spapr_caps: Add new tristate cap safe_bounds_check
  target/ppc/spapr_caps: Add new tristate cap safe_cache
  target/ppc/spapr_caps: Add support for tristate spapr_capabilities
  target/ppc/kvm: Add cap_ppc_safe_[cache/bounds_check/indirect_branch]
  spapr_pci: fix MSI/MSIX selection
  input: add missing newline from trace-events
  uninorth: convert to trace-events
  grackle: convert to trace-events
  ppc: Deprecate qemu-system-ppcemb
  ppc/pnv: fix PnvChip redefinition in <hw/ppc/pnv_xscom.h>

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>